单项选择题

Li Lei didn't meet the famous American professor （） he was on holiday in America last year.

A．unless
B．until
C．if
D．whether

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So （） after she learned the good news that she could ha...

单项选择题So （） after she learned the good news that she could hardly fall asleep that night.

A．excited the mother was
B．was the mother excited
C．the mother was excited
D．excited was the mother